<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta http-equiv="X-UA-Compatible" content="ie=edge" />
    <title>后盾人</title>
  </head>
  <body></body>
  <script>
    let hd = { name: "后盾人" };
    let edu = hd;
    let set = new WeakSet();
    set.add(hd);

    hd = null;
    edu = null;
    // setTimeout(() => {
    //   console.lolg(set);
    // }, 2000);

    // console.log(set);
    // console.log(set.keys());
    // for (const iterator of set) {
    // }
    // console.log(set);
    // console.log(set.size);
    // let a = new Set([1, 2]);
    // console.log(a.size);
  </script>
</html>
